Mateo Kovacic tests positive for Covid in ‘huge setback’ for Chelsea’s Tuchel

• Kovacic to miss games against Zenit, Leeds and Everton

• Midfielder was due to return from injury in Champions League

Chelsea’s problems in midfield have deepened after Mateo Kovacic tested positive for Covid-19 a day after returning to training from a lengthy absence with a hamstring injury.

Thomas Tuchel, who will be without N’Golo Kanté and Jorginho when Chelsea look to win their Champions League group by beating Zenit St Petersburg on Wednesday, had hoped to include Kovacic against Leeds on Saturday. The midfielder has not featured since 26 October and his presence in training on Monday was a boost, particularly as there is no timeframe on Kanté’s return from a knee injury and Jorginho has been playing through back and hip pain.

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Injuries have taken a toll on Chelsea, who have lost their place at the top of the Premier League, and Tuchel’s frustration increased when he received news that Kovacic has been forced to isolate for 10 days. The 27-year-old, who was unlikely to travel to Russia, must return a negative test before playing again and will be absent at home to Leeds on Saturday and Everton on 16 December.

“We have bad news because Mateo was in training yesterday with a big smile, pure pleasure to have him back, and he tested positive today for corona and is isolating,” Tuchel said. “He will be out for several days, which is a huge setback for him and me, and all of us. This is what reality is at the moment so we have to be ready to adapt and secure people’s health.”

Chelsea, who hope that Kovacic will be available at Wolves on 19 December, are short of options before facing Zenit. Ross Barkley is in the squad, Ruben Loftus-Cheek could start for the fourth consecutive game and there could be a rare start for Saúl Ñíguez, who has made little impact on a season’s loan from Atlético Madrid.

Saúl has struggled with the intensity of the Premier League and he was substituted at half-time when Chelsea beat Watford last week. “He needs rhythm and minutes,” Tuchel said. “We try to encourage him because he grows into Chelsea more and more.”

Tuchel denied that he had to be more careful with Kanté, who has struggled with injuries in the past two years. “I’m not so careful when to bring him back,” Chelsea’s manager said. “He takes care of his body and doesn’t want to take risks. He is a super man; the guy everyone in the whole world wants in his midfield. We built him up after his last injury. Now we have an accident. It’s not related to age or overload. It’s simply an accident during a match.”

Tuchel said he was worried about the physical demands on his squad before the festive period. Chelsea, who will be eager to bounce back from their sloppy defeat at West Ham, are waiting to find out whether a knee injury will keep Ben Chilwell out for the rest of the season. Trevoh Chalobah could return from a hamstring problem next week, and Marcos Alonso and Kai Havertz have shaken off knocks.